The present invention relates to an endoscope for high-frequency treatment used for incision or excision of mucous membranes of human tissues or the like using high-frequency electric current.
For performing incision or excision of mucous membranes of human tissues, a high-frequency treatment device such as a high-frequency snare is typically used. In case that the treatment does not go well even if the high-frequency treatment tool is inserted in a treatment tool insertion channel of the endoscope, there has been suggested an improved endoscope which has a hood detachably coupled to the tip of the endoscope body, and the hood is used as a base of the high-frequency treatment tool. An example of such an endoscope is disclosed in Japanese Patent Provisional Publication No. HEI 09-187415.
In the above publication, besides channel(s) formed in the endoscope body, another channel is provided outside the endoscope and the hood, and the high-frequency snare is inserted therethrough. According to this structure, depending on the high-frequency tool, lead lines for supplying electrical current to the electrodes of the high-frequency tool mounted on the hood may be run outside the inserting section of the endoscope.
In such a case, since the lead lines are swinging around the inserting section of the endoscope, a patient who swallows the inserting section suffers from pain. The lead lines are also troublesome for an operator since they may twine his/her hand and obstruct the operation of the endoscope. However, if the lead lines are inserted into the channel for a treatment tool, other tools such as a suction tool and the like cannot be used simultaneously.
The present invention is advantageous in that an improved endoscope for high-frequency treatment is provided. The endoscope has a detachably coupled tip hood that functions as a base for the high-frequency tools, and can be used without imposing burden to both the patient and the operator.
According to an aspect of the invention, there is provided an endoscope for high-frequency treatment, which includes a flexible inserting section to be inserted in a human cavity, an operation unit connected to a proximal end of the flexible inserting section, at least one terminal, which is connected to a high-frequency power supply, being provided to the operation unit, a hood provided with at least one treatment electrode for the high-frequency treatment, at least one contact and at least one conductive line connecting the treatment electrode and the contact, and a tip unit provided at a tip end of the inserting section, the tip unit being formed with a hood receiving portion to which the hood is detachably coupled, the tip unit being provided with at least one power supply electrode which contacts the at least one contact of the hood when the hood is coupled to the tip unit, the at least one power supply electrode being connected with the at least one terminal provided to the operation unit through a conductive wire which is inserted in the inserting section.
Optionally, there may be a pair of terminals which are connected to opposite outputs of the high-frequency power supply, a pair of treatment electrodes and a pair of contacts. The pair of treatment electrodes and the pair of contacts are connected with a pair of conductive lines, respectively. Further, there may be a pair of power supply electrodes which contact the pair of contacts of the hood, the pair of power supply electrodes being connected with the pair of terminals.
Further optionally, at least one groove may be formed on the outer surface of the terminal unit, the at least one power supply electrode being provided in the groove.
Still optionally, the at least one power supply electrode may be configured to resiliently deform, and when the hood is coupled to the tip end, the power supply electrode resiliently biases the contact to retain the hood in position.
In a particular case, the at least one conductive line may be embedded in a wall of the hood.
Optionally, a part of the at least one conductive line may be exposed to inside of a wall of the hood.
Further optionally, the hood is configured to fitted on the tip unit, a step being formed on an inner wall of the hood, the step contacting the end of the tip unit to position the hood in a depth direction.
Further optionally, the hood may be a hollow cylindrical member.